#include <stdio.h>
#include <unistd.h>
int main (void)
{
	//设置alarm, 1s
	alarm(5);
	for (int  i = 1; i < 90000; i++) {
		printf ("i = %d\n", i);
	}
	//取消闹钟
	int ret = alarm (0);
	printf ("ret = %d\n", ret);
	return 0;
}
